
Caltha leptosepala
Caltha leptosepala
Safety & Hazards
The whole plant, but especially the older portions, contains the toxic glycoside protoanemonin - this is destroyed by heat[1]. Symptoms of poisoning include a burning sensation in the throat, vomiting, bloody diarrhoea, dizziness, fainting, and, in large doses, convulsions. However, the toxicity is of a fairly low order and the plant would usually need to be eaten in quantity in order to cause major symptoms[2] The sap can irritate sensitive skin[1].
Cultivation Details
Caltha leptosepala has a very wide native range, from the Arctic of Alaska to the warm temperate climate of California and New Mexico. It can tolerate temperatures falling to around -20°c[3]. A plant of the waterside, it prefers growing in a sunny position in wet soils or shallow water[4, 5, 6], though it will tolerate drier conditions if there is shade from the summer sun[6]. It requires a deep rich slightly acidic soil[5, 7]. Grows well in heavy clay soils. A greedy plant, inhibiting the growth of nearby plants, especially legumes[8].
Propagation
Seed - best sown as soon as it is ripe in a cold frame in late summer[7]. Stand the pots in 2 - 3cm of water to keep the soil wet. The seed usually germinates in 1 - 3 months at 15°c[9]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in a tray of water in a cold frame until they are at least 15cm tall. Plant them out into their permanent positions in the summer. Division in early spring or autumn[7]. Very easy, larger clumps can be replanted direct into their permanent positions, though it is best to pot up smaller clumps and grow them on in a cold frame until they are rooting well. Plant them out in the summer or following spring. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-20. <temperate.theferns.info/plant/Caltha+leptosepala>
Pollinators
Bees, Beetles, Flies
References
- [1]Discovering Wild Plants - Alaska, W. Canada and the Northwest. — Schofield. J. J. · Alaska Northwest Books; Alaska · 2003 · ISBN 0882403699 ↩︎A nice guide to some useful plants in that area.
- [2]Poisonous Plants of North Carolina — http://www.ces.ncsu.edu/depts/hort/consumer/poison/poison.htm ↩︎An excellent concise but comprehensive guide to toxic plants that grow in N. Carolina. It lists even those plants that are of very low toxicity, including several well-known food plants such as carrots and potatoes.
- [3]Perennials. Volumes 1 and 2. — Phillips. R. & Rix. M. · Pan Books · 1991 · ISBN 0-330-30936-9 ↩︎Photographs of over 3,000 species and cultivars of ornamental plants together with brief cultivation notes, details of habitat etc.
- [4]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [5]Popular Hardy Perennials. — Sanders. T. W. · Collingridge · 1926 · ISBN - ↩︎A fairly wide range of perennial plants that can be grown in Britain and how to grow them.
- [6]Perennial Garden Plants — Thomas. G. S. · J. M. Dent & Sons, London. · 1990 · ISBN 0 460 86048 8 ↩︎A concise guide to a wide range of perennials. Lots of cultivation guides, very little on plant uses.
- [7]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [8]How to Enjoy your Weeds. — Hatfield. A. W. · Frederick Muller Ltd · 1977 · ISBN 0-584-10141-4 ↩︎Interesting reading.
- [9]Growing from Seed. Volume 3. — Bird. R. (Editor) · Thompson and Morgan. · 1989 · ISBN - ↩︎Very readable magazine with lots of information on propagation.
- [10]Flora of N. America — http://flora.huh.harvard.edu/fna/ ↩︎An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
- [11]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [12]Vascular Plants of the Pacific Northwest. — Hitchcock. C. L. · University of Washington Press · 1955 · ISBN - ↩︎A standard flora for Western N. America with lots of information on habitat etc. Five large volumes, it is not for the casual reader.
- [13]Edible Native Plants of the Rocky Mountains. — Harrington. H. D. · University of New Mexico Press · 1967 · ISBN 0-8623-0343-9 ↩︎A superb book. Very readable, it gives the results of the authors experiments with native edible plants.
- [14]Tanaka's Cyclopedia of Edible Plants of the World. — Tanaka. T. & Nakao S. · Keigaku Publishing; Tokyo · 1976 · ISBN - ↩︎The most comprehensive list of edible plants I've come across. Only the briefest entry for each species, though, and some of the entries are more than a little dubious. Not for the casual reader.
- [15]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
- [16]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.